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1.
Methods ; 220: 142-157, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37939912

RESUMO

This review aims to provide a comprehensive overview of recent advancements and applications of fluorescence imaging probes synthesized via MCRs (multicomponent reactions). These probes, also known as functional chromophores, belong to a currently investigated class of fluorophores that are presently being successfully applied in bioimaging experiments, especially in various living cell lineages. We describe some of the MCRs that have been employed in the synthesis of these probes and explore their applications in biological imaging, with an emphasis on cellular imaging. The review also discusses the challenges and future perspectives in the field, particularly considering the potential impact of MCR-based fluorescence imaging probes on advancing this field of research in the coming years. Considering that this area of research is relatively new and nearly a decade has passed since the first publication, this review also provides a historical perspective on this class of fluorophores, highlighting the pioneering works published between 2011 and 2016.


Assuntos
Corantes Fluorescentes , Imagem Óptica
2.
Cell Biochem Funct ; 42(5): e4086, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38956862

RESUMO

Wounds represent a growing global issue demanding increased attention. To expedite wound healing, technologies are under development, and light emitting diode (LED) devices of varying wavelengths are being explored for their stimulating influence on the healing process. This article presents a systematic literature review aiming to compile, organize, and analyze the impacts of LED devices on wound healing. This review is registered on the PROSPERO platform [CRD42023403870]. Two blinded authors conducted searches in the Pubmed, Web of Science, Scopus, Embase, and ScienceDirect databases. In vitro and in vivo experimental studies assessing LED utilization in the wound healing process were included. The search yielded 1010 studies, of which 27 were included in the review. It was identified that LED stimulates different healing pathways, promoting enhanced cell proliferation and migration, angiogenesis stimulation, increased collagen deposition, and modulation of the inflammatory response. Thus, it can be concluded that the LED stimulates cellular and molecular processes contingent on the utilized parameters. The effects depend on the standards used. Cell migration and proliferation were better influenced by green and red LED. The extracellular matrix components and angiogenesis were regulated by all wavelengths and the modulation of inflammation was mediated by green, red, and infrared LEDs.


Assuntos
Proliferação de Células , Cicatrização , Animais , Humanos , Movimento Celular , Luz , Fototerapia
3.
Planta Med ; 90(12): 938-948, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39159664

RESUMO

Withanolides are steroidal lactones commonly found in plants of the Solanaceae family that have significant medicinal value. In this study, three withanolides extracted from Iochroma arborescens leaves were isolated and characterized. These included withaphysalin F (3: ) and two newly identified epimeric compounds: 18R- and 18S-O-methyl-withaphysalin F (1: and 2: ). Their structures were elucidated by NMR, IR, MS, CD, and X-ray diffraction analysis, and their potential against cell proliferation and migration was investigated. The cytotoxic assay revealed activity against different tumor and non-tumor cell lines. (18S)-O-methyl-withaphysalin F (2: ) presented cell death effects after at least 6 hours of exposure. MDA-MB-231 cells were exposed to 0.06 and 0.6 µM of (18S)-O-methyl-withaphysalin F (2: ), and reductions in cell adhesion, migration, and clonogenicity were observed. Morphological analysis revealed negative regulation in filopodia, salience, and roughness, as well as alterations in cellular microarchitecture. These results provide clues as to the effects of (18S)-O-methyl-withaphysalin F (2: ), allowing new molecular modifications to improve potency and selectivity and increase our antineoplastic arsenal.


Assuntos
Antineoplásicos Fitogênicos , Movimento Celular , Proliferação de Células , Humanos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Vitanolídeos/farmacologia , Vitanolídeos/isolamento & purificação , Vitanolídeos/química , Solanaceae/química , Estrutura Molecular , Folhas de Planta/química
4.
Orthod Craniofac Res ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39003677

RESUMO

INTRODUCTION: The complete bilateral cleft lip and palate (BCLP) divides the maxillary arch into three segments, separated from each other, resulting in abnormal growth of the alveolar arch. This study evaluated the maxillary arch dimensions in BCLP and compared them with neonates without craniofacial anomalies. METHODS: This retrospective study was conducted in a tertiary cleft centre. Sixty-six neonates aged 0-5 months were divided into two groups: cleft group-children with BCLP (23 boys and 18 girls) and control group-children without craniofacial deformities (15 boys and 10 girls). The dental models were processed by a 3D scanner. Landmarks were marked to achieve inter-canine distance, inter-tuberosity distance and arch length measurements. t-Tests were used for intergroup comparisons (p < .05). RESULTS: The maxillary cleft arch was demonstrated to be wider and longer in the posterior region compared to the control group. The inter-canine distance did not present differences between the cleft and controls. The inter-canine distance of the control group was the only measurement influenced by the variable sex. CONCLUSIONS: The cleft significantly interfered with the arch posterior width and arch sagittal length, making them larger. There was no statistical difference in the measurements between sex in the cleft group.

5.
Gerontology ; 68(3): 261-271, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515129

RESUMO

INTRODUCTION: Computed tomography (CT) of the chest, although not a screening test or diagnosis of infection with the new coronavirus, has a fundamental role in assessing the extent of lung involvement and complications such as pleural effusion. Considering the higher morbidity and mortality of elderly patients due to this infection, the objective of this study was to evaluate the imaging aspects and clinical correlations of an extreme age (≥80 years) with a confirmed diagnosis for COVID-19. METHODS: This was a retrospective and single-center cohort study. CT scans were categorized qualitatively and quantitatively. In the first case, 3 descriptors were used to describe CT findings: "compatible" (findings of greater specificity for COVID-19: opacities with attenuation in ground glass with peripheral and bilateral distribution, with rounded morphology, with or without consolidations, crazy-pavement aspect, inverted halo sign, or organizing pneumonia findings), "doubtful" (findings not specific or unusual for COVID-19: opacities with attenuation in ground glass with nonrounded morphology, central, diffuse, or unilateral distribution, with or without consolidation, lobar or segmental consolidation without ground-glass opacity, small centrilobular nodules with the appearance of "tree-in-bud," excavations, pleural effusion, and thickening of interlobular septa), and "negative" (absence of pneumonia signs). For the quantitative assessment, which referred to the extent of pulmonary involvement, a tomographic severity classification was used: grade 1 (lung involvement ≤25%), grade 2 (pulmonary involvement between 26 and 50%), and grade 3 (pulmonary involvement >50%). RESULTS: A total of 138 patients were evaluated, with an average age of 86.2 years (84 women and 34 men). The mean time interval between onset of symptoms and tomography was 5.63 days. The most prevalent comorbidity was systemic arterial hypertension (81.2%). Compatible, doubtful, and negative tests were 117 (84.7%), 20 (14.4%), and 1 (0.7%), respectively. As for compatible exams, the most common findings were opacities in peripheral ground glass and rounded morphology, followed by crazy paving. The prevalence of pleural effusion was 28.2% and consolidation was 63.7%, and none of these findings were influenced by the duration of symptoms (p = 0.08 and p = 0.2, respectively). The exams classified as grade 1, grade 2, and grade 3 were 57 (41.6%), 46 (33.6%), and 34 (24.8%), respectively. There were statistically significant associations between the classification of tomographic severity and outcomes such as invasive ventilation (p = 0.004), admission to the intensive care unit (p < 0.001), and death (p < 0.001). DISCUSSION/CONCLUSION: Our results show that patients ≥80 years old present tomographic manifestations similar to those described for the general population (ground-glass opacities and "crazy paving") and that the extent of lung involvement is associated with the need for intensive care, invasive ventilation, and death. Although the literature describes an association between the stage of the disease and the appearance of consolidations and pleural effusion, this correlation was not observed in our study, which may suggest that this age-group is more predisposed to the appearance of such findings, typically described in the more advanced stages of infection.


Assuntos
COVID-19 , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
6.
J Med Syst ; 46(8): 55, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35788428

RESUMO

To describe the implementation of a standardized code system for notification of relevant expected or incidental findings in imaging exams and use of an automated textual mining tool of radiological report narratives, created to facilitate directing patients to specific lines of care, reducing the waiting time for interventions, consultations, and minimizing delays to treatment. We report our 12-month initial experience with the process. A standardized code was attached to every radiology report when a relevant finding was observed. On a daily basis, the notifications was sent to a dedicated medical team to review the notified abnormality and decide a proper action. Between October 1, 2020, and September 30, 2021, 40,296 sectional examinations (CT and MR scans) were evaluated in 35,944 patients. The main findings reported were calcified plaques on the trunk of the left coronary artery or trunk like, pulmonary nodule/mass and suspected liver disease. Data of follow-up was available in 10,019 patients. The age ranged from 24 to 101 years (mean of 71.3 years) and 6,626 were female (66.1%). In 2,548 patients a complementary study or procedure was indicated, and 3,300 patients were referred to a specialist. Customized database searches looking for critical or relevant findings may facilitate patient referral to specific care lines, reduce the waiting time for interventions or consultations, and minimize delays to treatment.


Assuntos
Diagnóstico por Imagem , Achados Incidentais , Adulto , Idoso , Idoso de 80 Anos ou mais , Atenção à Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Plant J ; 103(5): 1894-1909, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32445587

RESUMO

Soybean (Glycine max [L.] Merr.) is a major crop in animal feed and human nutrition, mainly for its rich protein and oil contents. The remarkable rise in soybean transcriptome studies over the past 5 years generated an enormous amount of RNA-seq data, encompassing various tissues, developmental conditions and genotypes. In this study, we have collected data from 1298 publicly available soybean transcriptome samples, processed the raw sequencing reads and mapped them to the soybean reference genome in a systematic fashion. We found that 94% of the annotated genes (52 737/56 044) had detectable expression in at least one sample. Unsupervised clustering revealed three major groups, comprising samples from aerial, underground and seed/seed-related parts. We found 452 genes with uniform and constant expression levels, supporting their roles as housekeeping genes. On the other hand, 1349 genes showed heavily biased expression patterns towards particular tissues. A transcript-level analysis revealed that 95% (70 963 of 74 490) of the assembled transcripts have intron chains exactly matching those from known transcripts, whereas 3256 assembled transcripts represent potentially novel splicing isoforms. The dataset compiled here constitute a new resource for the community, which can be downloaded or accessed through a user-friendly web interface at http://venanciogroup.uenf.br/resources/. This comprehensive transcriptome atlas will likely accelerate research on soybean genetics and genomics.


Assuntos
Atlas como Assunto , Glycine max/genética , RNA de Plantas/genética , Transcriptoma/genética , Perfilação da Expressão Gênica , Biblioteca Gênica , Genes Essenciais/genética , Genes de Plantas/genética
8.
Cell Microbiol ; 22(11): e13243, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32597009

RESUMO

Trypanosomatids regulate gene expression mainly at the post-transcriptional level through processing, exporting and stabilising mRNA and control of translation. In most eukaryotes, protein synthesis is regulated by phosphorylation of eukaryotic initiation factor 2 (eIF2) at serine 51. Phosphorylation halts overall translation by decreasing availability of initiator tRNAmet to form translating ribosomes. In trypanosomatids, the N-terminus of eIF2α is extended with threonine 169 the homologous phosphorylated residue. Here, we evaluated whether eIF2α phosphorylation varies during the Trypanosoma cruzi life cycle, the etiological agent of Chagas' disease. Total levels of eIF2α are diminished in infective and non-replicative trypomastigotes compared with proliferative forms from the intestine of the insect vector or amastigotes from mammalian cells, consistent with decreased protein synthesis reported in infective forms. eIF2α phosphorylation increases in proliferative intracellular forms prior to differentiation into trypomastigotes. Parasites overexpressing eIF2αT169A or with an endogenous CRISPR/Cas9-generated eIF2αT169A mutation were created and analysis revealed alterations to the proteome, largely unrelated to the presence of µORF in epimastigotes. eIF2αT169A mutant parasites produced fewer trypomastigotes with lower infectivity than wild type, with increased levels of sialylated mucins and oligomannose glycoproteins, and decreased galactofuranose epitopes and the surface protease GP63 on the cell surface. We conclude that eIF2α expression and phosphorylation levels affect proteins relevant for intracellular progression of T. cruzi.


Assuntos
Doença de Chagas/parasitologia , Fator de Iniciação 2 em Eucariotos/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/metabolismo , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Linhagem Celular Tumoral , Fator de Iniciação 2 em Eucariotos/genética , Regulação da Expressão Gênica , Humanos , Estágios do Ciclo de Vida , Mutação , Parasitemia , Fosforilação , Biossíntese de Proteínas , Proteoma/metabolismo , Proteínas de Protozoários/análise , Proteínas de Protozoários/biossíntese , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/patogenicidade , Virulência
9.
Org Biomol Chem ; 19(7): 1514-1531, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33332518

RESUMO

In this work, we describe the application of a synthetic enzyme (synzyme) as the catalyst to promote the multicomponent synthesis of isoxazol-5(4H)-one derivatives. The catalytic system could be used up to 15 times without any notable loss of its activity. Some derivatives showed fluorescence and their photophysical data were evaluated. The mechanism of the reaction was, for the first time, investigated and, among the three reaction pathway possibilities, only one was operating under the developed conditions. ESI-MS(/MS) allowed for both the simultaneous monitoring of the multicomponent reaction (MCR) and the proposition of a kinetic model to explain the transformation. The kinetic model pointed firmly to only one reaction pathway and helped to discard the other two possibilities. The antimicrobial abilities of all synthesized derivatives against Gram-positive and Gram-negative strains were also evaluated. The abilities of functional chromophores (fluorescent compounds) as live cell-imaging probes were verified and one of the multicomponent adducts could stain early endosomes selectively in bioimaging experiments.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Isoxazóis/farmacologia , Peptídeos/química , Antibacterianos/síntese química , Antibacterianos/química , Catálise , Isoxazóis/síntese química , Isoxazóis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular
10.
Planta ; 252(6): 104, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33196909

RESUMO

MAIN CONCLUSION: We report a soybean gene co-expression network built with data from 1284 RNA-Seq experiments, which was used to identify important regulators, modules and to elucidate the fates of gene duplicates. Soybean (Glycine max (L.) Merr.) is one of the most important crops worldwide, constituting a major source of protein and edible oil. Gene co-expression networks (GCN) have been extensively used to study transcriptional regulation and evolution of genes and genomes. Here, we report a soybean GCN using 1284 publicly available RNA-Seq samples from 15 distinct tissues. We found modules that are differentially regulated in specific tissues, comprising processes such as photosynthesis, gluconeogenesis, lignin metabolism, and response to biotic stress. We identified transcription factors among intramodular hubs, which probably integrate different pathways and shape the transcriptional landscape in different conditions. The top hubs for each module tend to encode proteins with critical roles, such as succinate dehydrogenase and RNA polymerase subunits. Importantly, gene essentiality was strongly correlated with degree centrality and essential hubs were enriched in genes involved in nucleic acids metabolism and regulation of cell replication. Using a guilt-by-association approach, we predicted functions for 93 of 106 hubs without functional description in soybean. Most of the duplicated genes had different transcriptional profiles, supporting their functional divergence, although paralogs originating from whole-genome duplications (WGD) are more often preserved in the same module than those from other mechanisms. Together, our results highlight the importance of GCN analysis in unraveling key functional aspects of the soybean genome, in particular those associated with hub genes and WGD events.


Assuntos
Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Glycine max , Perfilação da Expressão Gênica , Glycine max/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
J Proteome Res ; 15(6): 2039-51, 2016 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-27108550

RESUMO

Histones are well-conserved proteins that form the basic structure of chromatin in eukaryotes and undergo several post-translational modifications, which are important for the control of transcription, replication, DNA damage repair, and chromosome condensation. In early branched organisms, histones are less conserved and appear to contain alternative sites for modifications, which could reveal evolutionary unique functions of histone modifications in gene expression and other chromatin-based processes. Here, by using high-resolution mass spectrometry, we identified and quantified histone post-translational modifications in two life cycle stages of Trypanosoma cruzi, the protozoan parasite that causes Chagas disease. We detected 44 new modifications, namely: 18 acetylations, seven monomethylations, seven dimethylations, seven trimethylations, and four phosphorylations. We found that replicative (epimastigote stage) contains more histone modifications than nonreplicative and infective parasites (trypomastigote stage). Acetylations of lysines at the C-terminus of histone H2A and methylations of lysine 23 of histone H3 were found to be enriched in trypomastigotes. In contrast, phosphorylation in serine 23 of H2B and methylations of lysine 76 of histone H3 predominates in proliferative states. The presence of one or two methylations in the lysine 76 was found in cells undergoing mitosis and cytokinesis, typical of proliferating parasites. Our findings provide new insights into the role of histone modifications related to the control of gene expression and cell-cycle regulation in an early divergent organism.


Assuntos
Cromatina/química , Código das Histonas , Estágios do Ciclo de Vida , Proteômica/métodos , Acetilação , Ciclo Celular , Regulação da Expressão Gênica , Metilação , Fosforilação , Processamento de Proteína Pós-Traducional/fisiologia , Trypanosoma cruzi
13.
Glycobiology ; 24(2): 179-84, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24225883

RESUMO

The invasion of host cells by the intracellular protozoan Trypanosoma cruzi requires interactions with host cell molecules, and the replication of the parasite requires escape from a parasitophorous vacuole into the host cell cytosol. Galectin-3, a member of ß-galactosidase-binding lectin family, has numerous extracellular and intracellular functions. In this study, we investigated the role of galectin-3 during the invasion and intracellular trafficking of T. cruzi extracellular amastigotes (EAs). Endogenous galectin-3 from mouse peritoneal macrophages accumulated around the pathogen during cell invasion by EAs. In addition, galectin-3 accumulated around parasites after their escape from the parasitophorous vacuole. Thus, galectin-3 behaved as a novel marker of phagolysosome lysis during the infection of host cells by T. cruzi.


Assuntos
Galectina 3/metabolismo , Trypanosoma cruzi/fisiologia , Trypanosoma cruzi/patogenicidade , Animais , Transporte Biológico , Células Cultivadas , Citoplasma/parasitologia , Células-Tronco Embrionárias/parasitologia , Endocitose , Humanos , Macrófagos Peritoneais/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica
14.
Parasitol Res ; 113(6): 2303-10, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24744221

RESUMO

The aim of this study was to compare the liveweight gain of lambs, infected by multidrug-resistant nematodes, treated by conventional schemes of helminth control or using a schedule based on fecal egg count reduction test (FECRT). The flock was selected after a FECRT (experiment 1) which revealed a parasite population resistant to benzimidazoles, imidazothiazoles, macrocyclic lactones (ivermectin), salicylanilides, nitrophenols, and organophosphates. Despite the parasite resistance to ivermectin (an avermectin), the moxidectin (a milbemycin) was effective against the gastrointestinal nematodes (PR > 90%). In experiment 2, 48 suckling lambs were distributed in four randomized blocks (G1, G2, G3, and G4) by previous body weighings. G1 was kept as untreated control; G2 was treated following a FECRT-based schedule with drugs chosen based on fecal analysis (first drench with moxidectin, second drench with a combination of moxidectin and levamisole, and third drench with praziquantel, an anti-cestode drug); G3 and G4 received three drenches with ivermectin or disophenol, respectively. Body weighings and fecal analysis of these lambs were performed every 2 weeks over a 98-day period. An effective control of gastrointestinal nematodes was obtained with two nematicidal drenches following the FECRT-based schedule of treatments. On the other hand, eggs per gram of feces (EPG) counts were no different among untreated control, G3, and G4. Lambs treated using the FECRT-based schedule had the greatest liveweight gain among the groups tested. Additionally, liveweight gain was no different among the groups G3, G4, and G1. The FECRT-based schedule of anthelmintic treatments was beneficial regarding productivity and sustainability of helminth control in lambs infected by multidrug-resistant nematodes.


Assuntos
Antinematódeos/uso terapêutico , Resistência a Múltiplos Medicamentos , Nematoides/efeitos dos fármacos , Infecções por Nematoides/veterinária , Doenças dos Ovinos/parasitologia , Animais , Fezes/parasitologia , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Aumento de Peso
15.
Molecules ; 19(4): 4560-77, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24731985

RESUMO

The seasonal chemical composition of essential oils from Inga laurina was determined by GC/MS. In the stem bark's essential oil extracted during the dry season, the presence of terpenoids (30.05%) stood out, and phytol (9.76%) was the major compound identified. For the stem bark oil obtained during the rainy season, in addition to terpenoids (26.63%), a large amount of fatty acids (46.84%) were identified, in particular palmitic acid (25.40%). Regarding the leaves' essential oil obtained in the dry season, esters (42.35%) were the main components. The main ester present was (Z)-hex-3-enyl benzoate (10.15%) and the major compound of this oil was (Z)-hex-3-en-1-ol (14.23%). Terpenoids (33.84%), long-chain alkanes (27.04%) and fatty acids (21.72%) were the main components of the essential oil from leaves in the rainy season. Phytol (33.21%), nonacosane (21.95%) and palmitic acid (15.20%) were the major compounds identified. The antimicrobial activity against aerobic and anaerobic oral bacteria was evaluated by the microdilution broth method and cytotoxic activity was carried out with Vero cells. The essential oils from the rainy season showed a better inhibition of the bacterial growth with Minimal Inhibitory Concentrations (MIC) values of 25 or 50 µg·mL⁻¹ for aerobic bacteria, and high selectivity against bacteria was observed. The large amount of fatty acids in rainy season oils may be related to the better inhibitory effects observed.


Assuntos
Anti-Infecciosos/química , Citotoxinas/química , Fabaceae/química , Óleos Voláteis/química , Óleos de Plantas/química , Animais , Anti-Infecciosos/farmacologia , Bactérias Aeróbias/efeitos dos fármacos , Bactérias Aeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/efeitos dos fármacos , Bactérias Anaeróbias/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Citotoxinas/farmacologia , Ésteres , Ácidos Graxos/classificação , Ácidos Graxos/isolamento & purificação , Óleos Voláteis/farmacologia , Especificidade de Órgãos , Casca de Planta/química , Folhas de Planta/química , Óleos de Plantas/farmacologia , Estações do Ano , Terpenos/classificação , Terpenos/isolamento & purificação , Células Vero
16.
Foods ; 13(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39272509

RESUMO

Antioxidant films were prepared using poly(vinyl chloride) (PVC) incorporated with 0.5% or 1.0% zinc oxide (ZnO)-flavonoid (quercetin or morin) nanoparticles (NPZnO-Q% or NPZnO-M%) via the casting method. NP incorporation within the polymer matrix influenced the structural, morphological, optical, and thermal properties of the PVC-based films, as well as their antioxidant activity as assessed using the DPPH radical scavenging method. Our results indicated that increasing ZnO-flavonoid NP concentration increased films thickness, while reducing ultraviolet light (UV) transmittance but conserving transparency. The presence of NPZnO-Q% or NPZnO-M% improved the surface uniformity and thermal stability of the active films. In terms of antioxidant activity, there was an enhancement in the DPPH radical scavenging capacity (PVC/ZnO-Q1.0% > PVC/ZnO-Q0.5% > PVC/ZnO-M0.5% > PVC/ZnO-M1.0% > PVC), suggesting that the packaging can help protect food from oxidative processes. Therefore, these antioxidant films represent an innovative strategy for using as active food packaging material, especially intended for aiding in quality preservation and extending the shelf life of fatty foods.

17.
J Chemother ; 36(3): 222-237, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37800867

RESUMO

Countless efforts have been made to prevent and suppress the formation and spread of melanoma. Natural astaxanthin (AST; extracted from the alga Haematococcus pluvialis) showed an antitumor effect on various cancer cell lines due to its interaction with the cell membrane. This study aimed to characterize the antitumor effect of AST against B16F10-Nex2 murine melanoma cells using cell viability assay and evaluate its mechanism of action using electron microscopy, western blotting analysis, terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, and mitochondrial membrane potential determination. Astaxanthin exhibited a significant cytotoxic effect in murine melanoma cells with features of apoptosis and autophagy. Astaxanthin also decreased cell migration and invasion in vitro assays at subtoxic concentrations. In addition, assays were conducted in metastatic cancer models in mice where AST significantly decreased the development of pulmonary nodules. In conclusion, AST has cytotoxic effect in melanoma cells and inhibits cell migration and invasion, indicating a promising use in cancer treatment.


Assuntos
Antineoplásicos , Melanoma Experimental , Camundongos , Animais , Linhagem Celular Tumoral , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Apoptose , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Autofagia , Proliferação de Células , Camundongos Endogâmicos C57BL , Xantofilas
18.
Nat Commun ; 15(1): 3137, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605004

RESUMO

Laser Sintering (LS) is a type of Additive Manufacturing (AM) exploiting laser processing of polymeric particles to produce 3D objects. Because of its ease of processability and thermo-physical properties, polyamide-12 (PA-12) represents ~95% of the polymeric materials used in LS. This constrains the functionality of the items produced, including limited available colours. Moreover, PA-12 objects tend to biofoul in wet environments. Therefore, a key challenge is to develop an inexpensive route to introduce desirable functionality to PA-12. We report a facile, clean, and scalable approach to modification of PA-12, exploiting supercritical carbon dioxide (scCO2) and free radical polymerizations to yield functionalised PA-12 materials. These can be easily printed using commercial apparatus. We demonstrate the potential by creating coloured PA-12 materials and show that the same approach can be utilized to create anti-biofouling objects. Our approach to functionalise materials could open significant new applications for AM.

19.
Molecules ; 18(4): 4588-98, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23599016

RESUMO

The chemical composition of the essential oils from leaves, bark and wood of Cassia bakeriana Craib. was determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Alcohols, aldehydes and fatty acids were the major components in leaf and bark oil, while wood essential oil was rich in fatty acids. Terpenes such as linalool, (E)-nerolidol and phytol were present in low concentrations. The antimicrobial activity against aerobic and anaerobic oral bacteria was evaluated using the microdilution method, as was the cell viability test carried out with Vero cells. The oils from leaves and bark showed high antimicrobial activity, with minimum inhibitory concentrations between 62.5 and 125 µg·mL⁻¹ for most of the tested bacteria, including Streptococcus mutans, the main etiological agent of dental caries. Leaves oil displayed the lowest cytotoxic effect (EC50 of 153 µg·mL⁻¹), while wood oil exhibited the highest toxicity to Vero cells. C. bakeriana oils are thus a source of biologically active compounds against aerobic and anaerobic oral microorganisms. This study is the first report on the chemical composition, antimicrobial activity and cytotoxicity of C. bakeriana.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias Aeróbias/efeitos dos fármacos , Bactérias Anaeróbias/efeitos dos fármacos , Cassia/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Animais , Anti-Infecciosos/toxicidade , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Cárie Dentária/microbiologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/toxicidade , Streptococcus mutans/efeitos dos fármacos , Células Vero
20.
Biotechnol J ; 18(8): e2200542, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37148557

RESUMO

A modification of the conventional batch organosolv process is proposed in a way where the solid biomass remains inside a basket, physically separated from the liquid phase, with the vapor promoting the fractionation of the biomass and the extracted compounds and fragments being washed down to the liquid phase. The modified organosolv process applied to sugarcane bagasse (SB-M) delivers a rich cellulosic solid phase that after enzymatic hydrolysis leads to a hydrolyzed with approximately 100 g L-1 of glucose. At the same enzymatic hydrolysis conditions, the conventional organosolv process (SB-C) delivers a hydrolyzed with 80 g L-1 of glucose, while the autohydrolysis process (SB-A) leads to 55 g L-1 of glucose. These different results are related to the cellulose content: SB-M (70%), SB-C (57%), e SB-A (44%), as well the reduced lignin content in the SB-M. The novelty of this study is the confirmation that it is possible to degrade lignin from sugarcane bagasse and simultaneously remove its fragments from the cellulose fibers in a batch reactor containing an internal basket. This study describes a simple and rapid protocol for the isolation of the main components of lignocellulosic biomass (cellulose, hemicellulose, and lignin), which may lead to the study of new catalysts for the chemical transformation of these components separately or simultaneously to the step of pretreatment.


Assuntos
Celulose , Saccharum , Celulose/metabolismo , Lignina/metabolismo , Saccharum/química , Saccharum/metabolismo , Glucose/metabolismo , Hidrólise
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